Very recently, molecular diagnostics has increasingly gained in importance. It has found an entry into the clinical diagnosis of diseases (inter alia detection of infectious pathogens, detection of mutations of the genome, detection of diseased cells and identification of risk factors for predisposition to a disease).
In particular, through the determination of gene expression in tissues, nucleic acid analysis opens up very promising new possibilities in the study and diagnosis of disease.
Nucleic acids of interest to be detected include genomic DNA, expressed mRNA and other RNAs such as MicroRNAs (abbreviated miRNAs). MiRNAs are a new class of small RNAs with various biological functions (A. Keller et al., Nat Methods. 2011 8(10):841-3). They are short (average of 20-24 nucleotide) ribonucleic acid (RNA) molecules found in eukaryotic cells. Several hundred different species of microRNAs (i.e. several hundred different sequences) have been identified in mammals. They are important for post-transcriptional gene-regulation and bind to complementary sequences on target messenger RNA transcripts (mRNAs), which can lead to translational repression or target degradation and gene silencing. As such they can also be used as biologic markers for research, diagnosis and therapy purposes.
Parkinson's disease (P) is a degenerative disorder of the central nervous system. The motor symptoms of Parkinson's disease result from the death of dopamine-generating cells in the nervous system; the cause of this cell death is unknown.
Early symptoms are often mistaken to be age-related problems. Parkinson's disease affects movement, producing motor symptoms and may cause mood, cognition, behavior or thought alterations. Diagnosis of Parkinson's disease is based on the medical history and a neurological examination. There is no lab test that will clearly identify the disease, but imaging modalities are sometimes used to rule out other disorders.
Symptoms, such as frailty and motor symptoms can be similar to other neurological disorders. Diagnosis can be time consuming, expensive and difficult. In particular, the reliable and early diagnosis of Parkinson based on non-invasive molecular biomarkers remains a challenge.
Therefore, there exists an unmet need for an efficient, simple, reliable diagnostic test for PD.